/Engine/Plugins/Online/OnlineSubsystem/Source/Public/OnlineKeyValuePair.h
the stringified version of the enum passed in
namespace EOnlineKeyValuePairDataType { const TCHAR * EOnlineKeyValuePairDataType::ToString ( [EOnlineKeyValuePairDataType::Type](API\Plugins\OnlineSubsystem\EOnlineKeyValuePairDataType__Typ-) EnumVal ) }